kernel-aes67/drivers/md/dm-vdo/vio.c

501 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2023 Red Hat
*/
#include "vio.h"
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/kernel.h>
#include <linux/ratelimit.h>
#include "logger.h"
#include "memory-alloc.h"
#include "permassert.h"
#include "constants.h"
#include "io-submitter.h"
#include "vdo.h"
/* A vio_pool is a collection of preallocated vios. */
struct vio_pool {
/* The number of objects managed by the pool */
size_t size;
/* The list of objects which are available */
struct list_head available;
/* The queue of requestors waiting for objects from the pool */
struct vdo_wait_queue waiting;
/* The number of objects currently in use */
size_t busy_count;
/* The list of objects which are in use */
struct list_head busy;
/* The ID of the thread on which this pool may be used */
thread_id_t thread_id;
/* The buffer backing the pool's vios */
char *buffer;
/* The pool entries */
struct pooled_vio vios[];
};
physical_block_number_t pbn_from_vio_bio(struct bio *bio)
{
struct vio *vio = bio->bi_private;
struct vdo *vdo = vio->completion.vdo;
physical_block_number_t pbn = bio->bi_iter.bi_sector / VDO_SECTORS_PER_BLOCK;
return ((pbn == VDO_GEOMETRY_BLOCK_LOCATION) ? pbn : pbn + vdo->geometry.bio_offset);
}
static int create_multi_block_bio(block_count_t size, struct bio **bio_ptr)
{
struct bio *bio = NULL;
int result;
result = vdo_allocate_extended(struct bio, size + 1, struct bio_vec,
"bio", &bio);
if (result != VDO_SUCCESS)
return result;
*bio_ptr = bio;
return VDO_SUCCESS;
}
int vdo_create_bio(struct bio **bio_ptr)
{
return create_multi_block_bio(1, bio_ptr);
}
void vdo_free_bio(struct bio *bio)
{
if (bio == NULL)
return;
bio_uninit(bio);
vdo_free(vdo_forget(bio));
}
int allocate_vio_components(struct vdo *vdo, enum vio_type vio_type,
enum vio_priority priority, void *parent,
unsigned int block_count, char *data, struct vio *vio)
{
struct bio *bio;
int result;
result = VDO_ASSERT(block_count <= MAX_BLOCKS_PER_VIO,
"block count %u does not exceed maximum %u", block_count,
MAX_BLOCKS_PER_VIO);
if (result != VDO_SUCCESS)
return result;
result = VDO_ASSERT(((vio_type != VIO_TYPE_UNINITIALIZED) && (vio_type != VIO_TYPE_DATA)),
"%d is a metadata type", vio_type);
if (result != VDO_SUCCESS)
return result;
result = create_multi_block_bio(block_count, &bio);
if (result != VDO_SUCCESS)
return result;
initialize_vio(vio, bio, block_count, vio_type, priority, vdo);
vio->completion.parent = parent;
vio->data = data;
return VDO_SUCCESS;
}
/**
* create_multi_block_metadata_vio() - Create a vio.
* @vdo: The vdo on which the vio will operate.
* @vio_type: The type of vio to create.
* @priority: The relative priority to assign to the vio.
* @parent: The parent of the vio.
* @block_count: The size of the vio in blocks.
* @data: The buffer.
* @vio_ptr: A pointer to hold the new vio.
*
* Return: VDO_SUCCESS or an error.
*/
int create_multi_block_metadata_vio(struct vdo *vdo, enum vio_type vio_type,
enum vio_priority priority, void *parent,
unsigned int block_count, char *data,
struct vio **vio_ptr)
{
struct vio *vio;
int result;
BUILD_BUG_ON(sizeof(struct vio) > 256);
/*
* Metadata vios should use direct allocation and not use the buffer pool, which is
* reserved for submissions from the linux block layer.
*/
result = vdo_allocate(1, struct vio, __func__, &vio);
if (result != VDO_SUCCESS) {
vdo_log_error("metadata vio allocation failure %d", result);
return result;
}
result = allocate_vio_components(vdo, vio_type, priority, parent, block_count,
data, vio);
if (result != VDO_SUCCESS) {
vdo_free(vio);
return result;
}
*vio_ptr = vio;
return VDO_SUCCESS;
}
/**
* free_vio_components() - Free the components of a vio embedded in a larger structure.
* @vio: The vio to destroy
*/
void free_vio_components(struct vio *vio)
{
if (vio == NULL)
return;
BUG_ON(is_data_vio(vio));
vdo_free_bio(vdo_forget(vio->bio));
}
/**
* free_vio() - Destroy a vio.
* @vio: The vio to destroy.
*/
void free_vio(struct vio *vio)
{
free_vio_components(vio);
vdo_free(vio);
}
/* Set bio properties for a VDO read or write. */
void vdo_set_bio_properties(struct bio *bio, struct vio *vio, bio_end_io_t callback,
blk_opf_t bi_opf, physical_block_number_t pbn)
{
struct vdo *vdo = vio->completion.vdo;
struct device_config *config = vdo->device_config;
pbn -= vdo->geometry.bio_offset;
vio->bio_zone = ((pbn / config->thread_counts.bio_rotation_interval) %
config->thread_counts.bio_threads);
bio->bi_private = vio;
bio->bi_end_io = callback;
bio->bi_opf = bi_opf;
bio->bi_iter.bi_sector = pbn * VDO_SECTORS_PER_BLOCK;
}
/*
* Prepares the bio to perform IO with the specified buffer. May only be used on a VDO-allocated
* bio, as it assumes the bio wraps a 4k buffer that is 4k aligned, but there does not have to be a
* vio associated with the bio.
*/
int vio_reset_bio(struct vio *vio, char *data, bio_end_io_t callback,
blk_opf_t bi_opf, physical_block_number_t pbn)
{
int bvec_count, offset, len, i;
struct bio *bio = vio->bio;
bio_reset(bio, bio->bi_bdev, bi_opf);
vdo_set_bio_properties(bio, vio, callback, bi_opf, pbn);
if (data == NULL)
return VDO_SUCCESS;
bio->bi_io_vec = bio->bi_inline_vecs;
bio->bi_max_vecs = vio->block_count + 1;
len = VDO_BLOCK_SIZE * vio->block_count;
offset = offset_in_page(data);
bvec_count = DIV_ROUND_UP(offset + len, PAGE_SIZE);
/*
* If we knew that data was always on one page, or contiguous pages, we wouldn't need the
* loop. But if we're using vmalloc, it's not impossible that the data is in different
* pages that can't be merged in bio_add_page...
*/
for (i = 0; (i < bvec_count) && (len > 0); i++) {
struct page *page;
int bytes_added;
int bytes = PAGE_SIZE - offset;
if (bytes > len)
bytes = len;
page = is_vmalloc_addr(data) ? vmalloc_to_page(data) : virt_to_page(data);
bytes_added = bio_add_page(bio, page, bytes, offset);
if (bytes_added != bytes) {
return vdo_log_error_strerror(VDO_BIO_CREATION_FAILED,
"Could only add %i bytes to bio",
bytes_added);
}
data += bytes;
len -= bytes;
offset = 0;
}
return VDO_SUCCESS;
}
/**
* update_vio_error_stats() - Update per-vio error stats and log the error.
* @vio: The vio which got an error.
* @format: The format of the message to log (a printf style format).
*/
void update_vio_error_stats(struct vio *vio, const char *format, ...)
{
static DEFINE_RATELIMIT_STATE(error_limiter, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
va_list args;
int priority;
struct vdo *vdo = vio->completion.vdo;
switch (vio->completion.result) {
case VDO_READ_ONLY:
atomic64_inc(&vdo->stats.read_only_error_count);
return;
case VDO_NO_SPACE:
atomic64_inc(&vdo->stats.no_space_error_count);
priority = VDO_LOG_DEBUG;
break;
default:
priority = VDO_LOG_ERR;
}
if (!__ratelimit(&error_limiter))
return;
va_start(args, format);
vdo_vlog_strerror(priority, vio->completion.result, VDO_LOGGING_MODULE_NAME,
format, args);
va_end(args);
}
void vio_record_metadata_io_error(struct vio *vio)
{
const char *description;
physical_block_number_t pbn = pbn_from_vio_bio(vio->bio);
if (bio_op(vio->bio) == REQ_OP_READ) {
description = "read";
} else if ((vio->bio->bi_opf & REQ_PREFLUSH) == REQ_PREFLUSH) {
description = (((vio->bio->bi_opf & REQ_FUA) == REQ_FUA) ?
"write+preflush+fua" :
"write+preflush");
} else if ((vio->bio->bi_opf & REQ_FUA) == REQ_FUA) {
description = "write+fua";
} else {
description = "write";
}
update_vio_error_stats(vio,
"Completing %s vio of type %u for physical block %llu with error",
description, vio->type, (unsigned long long) pbn);
}
/**
* make_vio_pool() - Create a new vio pool.
* @vdo: The vdo.
* @pool_size: The number of vios in the pool.
* @thread_id: The ID of the thread using this pool.
* @vio_type: The type of vios in the pool.
* @priority: The priority with which vios from the pool should be enqueued.
* @context: The context that each entry will have.
* @pool_ptr: The resulting pool.
*
* Return: A success or error code.
*/
int make_vio_pool(struct vdo *vdo, size_t pool_size, thread_id_t thread_id,
enum vio_type vio_type, enum vio_priority priority, void *context,
struct vio_pool **pool_ptr)
{
struct vio_pool *pool;
char *ptr;
int result;
result = vdo_allocate_extended(struct vio_pool, pool_size, struct pooled_vio,
__func__, &pool);
if (result != VDO_SUCCESS)
return result;
pool->thread_id = thread_id;
INIT_LIST_HEAD(&pool->available);
INIT_LIST_HEAD(&pool->busy);
result = vdo_allocate(pool_size * VDO_BLOCK_SIZE, char,
"VIO pool buffer", &pool->buffer);
if (result != VDO_SUCCESS) {
free_vio_pool(pool);
return result;
}
ptr = pool->buffer;
for (pool->size = 0; pool->size < pool_size; pool->size++, ptr += VDO_BLOCK_SIZE) {
struct pooled_vio *pooled = &pool->vios[pool->size];
result = allocate_vio_components(vdo, vio_type, priority, NULL, 1, ptr,
&pooled->vio);
if (result != VDO_SUCCESS) {
free_vio_pool(pool);
return result;
}
pooled->context = context;
list_add_tail(&pooled->pool_entry, &pool->available);
}
*pool_ptr = pool;
return VDO_SUCCESS;
}
/**
* free_vio_pool() - Destroy a vio pool.
* @pool: The pool to free.
*/
void free_vio_pool(struct vio_pool *pool)
{
struct pooled_vio *pooled, *tmp;
if (pool == NULL)
return;
/* Remove all available vios from the object pool. */
VDO_ASSERT_LOG_ONLY(!vdo_waitq_has_waiters(&pool->waiting),
"VIO pool must not have any waiters when being freed");
VDO_ASSERT_LOG_ONLY((pool->busy_count == 0),
"VIO pool must not have %zu busy entries when being freed",
pool->busy_count);
VDO_ASSERT_LOG_ONLY(list_empty(&pool->busy),
"VIO pool must not have busy entries when being freed");
list_for_each_entry_safe(pooled, tmp, &pool->available, pool_entry) {
list_del(&pooled->pool_entry);
free_vio_components(&pooled->vio);
pool->size--;
}
VDO_ASSERT_LOG_ONLY(pool->size == 0,
"VIO pool must not have missing entries when being freed");
vdo_free(vdo_forget(pool->buffer));
vdo_free(pool);
}
/**
* is_vio_pool_busy() - Check whether an vio pool has outstanding entries.
*
* Return: true if the pool is busy.
*/
bool is_vio_pool_busy(struct vio_pool *pool)
{
return (pool->busy_count != 0);
}
/**
* acquire_vio_from_pool() - Acquire a vio and buffer from the pool (asynchronous).
* @pool: The vio pool.
* @waiter: Object that is requesting a vio.
*/
void acquire_vio_from_pool(struct vio_pool *pool, struct vdo_waiter *waiter)
{
struct pooled_vio *pooled;
VDO_ASSERT_LOG_ONLY((pool->thread_id == vdo_get_callback_thread_id()),
"acquire from active vio_pool called from correct thread");
if (list_empty(&pool->available)) {
vdo_waitq_enqueue_waiter(&pool->waiting, waiter);
return;
}
pooled = list_first_entry(&pool->available, struct pooled_vio, pool_entry);
pool->busy_count++;
list_move_tail(&pooled->pool_entry, &pool->busy);
(*waiter->callback)(waiter, pooled);
}
/**
* return_vio_to_pool() - Return a vio to the pool
* @pool: The vio pool.
* @vio: The pooled vio to return.
*/
void return_vio_to_pool(struct vio_pool *pool, struct pooled_vio *vio)
{
VDO_ASSERT_LOG_ONLY((pool->thread_id == vdo_get_callback_thread_id()),
"vio pool entry returned on same thread as it was acquired");
vio->vio.completion.error_handler = NULL;
vio->vio.completion.parent = NULL;
if (vdo_waitq_has_waiters(&pool->waiting)) {
vdo_waitq_notify_next_waiter(&pool->waiting, NULL, vio);
return;
}
list_move_tail(&vio->pool_entry, &pool->available);
--pool->busy_count;
}
/*
* Various counting functions for statistics.
* These are used for bios coming into VDO, as well as bios generated by VDO.
*/
void vdo_count_bios(struct atomic_bio_stats *bio_stats, struct bio *bio)
{
if (((bio->bi_opf & REQ_PREFLUSH) != 0) && (bio->bi_iter.bi_size == 0)) {
atomic64_inc(&bio_stats->empty_flush);
atomic64_inc(&bio_stats->flush);
return;
}
switch (bio_op(bio)) {
case REQ_OP_WRITE:
atomic64_inc(&bio_stats->write);
break;
case REQ_OP_READ:
atomic64_inc(&bio_stats->read);
break;
case REQ_OP_DISCARD:
atomic64_inc(&bio_stats->discard);
break;
/*
* All other operations are filtered out in dmvdo.c, or not created by VDO, so
* shouldn't exist.
*/
default:
VDO_ASSERT_LOG_ONLY(0, "Bio operation %d not a write, read, discard, or empty flush",
bio_op(bio));
}
if ((bio->bi_opf & REQ_PREFLUSH) != 0)
atomic64_inc(&bio_stats->flush);
if (bio->bi_opf & REQ_FUA)
atomic64_inc(&bio_stats->fua);
}
static void count_all_bios_completed(struct vio *vio, struct bio *bio)
{
struct atomic_statistics *stats = &vio->completion.vdo->stats;
if (is_data_vio(vio)) {
vdo_count_bios(&stats->bios_out_completed, bio);
return;
}
vdo_count_bios(&stats->bios_meta_completed, bio);
if (vio->type == VIO_TYPE_RECOVERY_JOURNAL)
vdo_count_bios(&stats->bios_journal_completed, bio);
else if (vio->type == VIO_TYPE_BLOCK_MAP)
vdo_count_bios(&stats->bios_page_cache_completed, bio);
}
void vdo_count_completed_bios(struct bio *bio)
{
struct vio *vio = (struct vio *) bio->bi_private;
atomic64_inc(&vio->completion.vdo->stats.bios_completed);
count_all_bios_completed(vio, bio);
}